All-porcelain electrical lamp-socket.



E. H. FREEMAN.

ALL PORCELAIN ELECTRICAL LAMP SOCKET.

APPLICATION FILED APR. 1, 1910. I 1,005,635, Patented Oct. 10, 1911.

M43 hi lVfT/VESSES [/VVENTOR pi i TED 4 STATES} rarnnr enrich.

EDGAR H. FREEMAN, OF TRENTON, vNLN JERSEY.

ALL-PORCELAIN ELECTRICAL LAMP-SOCKET:

To all yak 0m it may concern:

Be it known. that I, EDGAR H. FREEMAN, a citizen of the United States, residing at Trenton, in the county of Mercer and State of New Jersey, have invented certam new' and useful Improvement in All-Porcelain Electrical Lamp-Sockets, of which the following is a specification.

This invention relates to the subject of electrical lamp sockets of the key-type and has particularly in view an improvement in that class of electrical incandescent lamp sockets which are known as all-porcelain sockets, and are intended to entirely dispense with the use of the usual outer metallic shell and cap ordinarily employed in The invention also contemplates a-novel construction and arrangement of elements 'which secure a thorough and complete i nsulation of opposite polarity parts, while.

at the same time completely housing and concealing all metallic parts within the socket structure so that none of the same are exposed to outside conditions or influ-.

ences. Furthermore, in the same connection,'the invention is intended to provide a compact arrangement of parts securing the greatest eficiency in the making and break ing of the electrical circuit through the switch mechanism and the related elements.

Another practical and important feature of the present invention residesin simple and novel means for holding the two parts of the socket together and permitting of their ready separation and assembling for wiring purposes without the possibility of parts becoming loose and falling out durmg such manipulation of the socket.

With these and many other, objects in View, which will be readily apparent to those familiar with the art as the nature of the invention is better understood, the same Specification of Letters Patent.

Application filed April 1, 1910. Serial No. 552,799.

Patented Oct. 16, 19i1.

consists in the novel construction, combination and arrangement of parts hereinafter fully described, illustrated and claimed.

The essential features of the invention involved in the carrying out of the abovementioned objects are susceptible to struc-.

tural modifications without departing from the Spirit or scope thereof, but the preferred and "practical details ofconstruction are shown in the accompanying drawings in which,

Figure 1 is a front end view of an allporcelain lamp socket constructed in accordance with the present invention. Fig. 2 is a longitudinal sectional viewthereof. Fig. 3 is a similar view on the line 38 of Fig. 1. Fig. 4c is an inner plan or face view of the porcelain cap-piece'showing the wire terminal plates carried thereby. Fig. 5 is an end elevation or face view of the inner end partof the socket body, showing the switch mechanism seated therein. Fig. 6 is a detail in perspective of the removable two-part switch frame which carries the key-shaft of the switch mechanism, the keyshaft and the switch dotted lines.

Like references designate corresponding parts in the several figures of the drawings.

The improved all-porcelain socket forming the subject-matter of this application includes in its general organization a socket body 1 of porcelain or equivalent insulating material'and a cap-piece or cap 2 likewise of porcelain or equivalent insulating ma terial, said cap surmounting what may be termed the inner end of the socket body and forming a part of the latter when united thereto through the medium of the fastening devices hereinafter particularly referred to. The porcelain body 1 and cap 2 and are flush fitting so as to present prac' tieally an unbroken external body of porcelain, within which body is completely housed and protected the various metallic parts making up the socket "contacts and switch mechanism. The cap-piece 2 is provided withthe ordinary wiring hole 3'for the line wires, and upon its inner face the said cap-piece is formed with'the separate plate recesses 4 and5 which respectively receive the opposite, opposite polarity, wire terminal plates 6 and 7. The wire terminal plate 6 ishel'd in a fixed position upon the inner side of the cap 2 within the recess 4 lu bein shown in preferably preserve the conventional design mounted in the body of the cap. The said plate 6 also carries a binding screw 9 for one of the line wires and includes as a part thereof an integral fixed contact platee'xtension 10 forming one of the elements of the switch mechanism, as will. hereinafter presently appear. The "other of said plate recesses 5, and likewise the wire terminal plate 7 therein, is ofa circular or segmental form, and the said" plate 7 is held in a fixed position within said recess by means of securing screws 11 suitably mounted in the body of the cap 2. The fixed wire terminal plate 7 'is provided at a suitable point between its extremities with a binding screw 12- for the other line wire, and by reason of the segmental form of the plate 7 the opposite termlnals thereof are widely separated, that is to say, they are located at diametrically; opposite sides of the wiring hole 3 through the cap, and these terminals of the plate 7 are provided with threaded o enings 13 which are adapted to detach: a ly receive the threaded end portions 14 of the combined fastening and conducting screws 15 which extend through screwholes 16 in the solid base portion 17 of the body 1. The combined fastening and conducting screws 15 are also arranged to have their headed ends engage with and hold the retaining flange18 provided at the inner end of the screw-shell contact 19 arranged within the plug-receiving socket 20'of the socket body 1. The threaded portions 1 1 of these screws have fitted thereonretainiug collars or rings 21 which are located between one face of the base 7 of the body and the wire terminal plate 7 with which the said screws engage. Between this plate 7 and clearance recesses 22 in the base 7, the

collars or rings 21 are designed to havea play so as not to interfere at all with the tightening and loosening of the screws 15, but in connection with this construction it will be observed that by reason of the retaining collars or\rings 21 it is possible to release the cap 2 from the socket body without disturbing or loosening any of the other elements of the socket or the wiring connections with the terminal plates 6 and 7; that is to. say, when the screws 15 are unscrewed from the openings or holes 13 in the plate 7, the cap will be released from the body and the screws will be held from falling out of the shell 19 by the holding engagement of the elements 21 on the base 17. It will thus be seen that the screws 15 perform several functions, namely, to hold the screw-shell contact. in place, to carry current from the screw-shell contact to the wire terminal plate 7, and to detachably unite the cap to the body, all of which is of practical importance in the manipulation of a socket of this character.

.of a folded contact member 31 and a sepa The switch mechanism for. the socket is, with the exception of the fixed contact plate 10, completely housed Within a substantially T-shaped-switch chamber 23, recessed in the inner face of the solid base 7 of the socket body and to provide for as complete insulation of the switch mechanism as possible,

the base 7 is formed about the edges of the chamber 23 with supporting shoulders 24 upon which are seated the edges'of a sheet. of mica or equivalent insulation-25. Theswitoh mechanism includes in its organization a two-part switch frame 26'detachably held within the switch chamber '23, and the key-shaft 27 carrying the rotatable switchblock 28 and the exterior switch-key 29. This key 29 is, according to the present in vention preferably made of porcelain to carry out the all-"porcelain idea, and the rotatable switch block 28 is of the conventional type, that is to say, having a limited play upon the shaft 27 but rotatable therewith so as to make and break the contact. The key-shaft 27 extends through a keyslot 30 in the wall of the body 1 and also. through opposite bearings in the two part switch frame 26. The two-part switch frame 26 of the switch mechanism consists rate bearing member 32. The folded contact member 31 is provided with a longitudinally arranged approxinriately T -shaped spring contact 33, the head of which has a constant spring engagement with the switch-block and said member 31 also IlIlcludes an angularly arranged bearing arm 34 in which is journaled one end of the keyshaft 27. The bearing member 32 of the two-part switch frame 26 consists of an angled slotted plate whose slot 35 is sufficiently large to receive therethrough the loop of the contact member 31 and is also formed -to provide one of the bearings for the key so that the overlapping parts receive there- 1 through the combined fastening and conducting screw 36, which passes through the bottom portion of the socket body and also passes through one arm of the folded center plug contact plate 37 held upon the bottom ofthe plug-receiving socket 20 of the body 1. The screw 36 therefore not only holds the center plug contact in position but it also holds in place the switch-frame, and holds together the two members of said frame, besides providing an electrical conductor between the center' plug contact and 25 the switch frame.

When the parts are in the assembled positions described, the fixed contact 10 carried by the cap 2 lies in opposition to the head of the spring contact 33 so that when the switch block is rotated to the proper position it will metallically, and therefore electrically, connect the said spring contact and the said fixed contact 10. In this connection, it will be observed that suificient clearance is left by the insulating sheet 25 to permit the ends of the switch block 28 passing out of the switchv chamber 23 to make engagement with the fixed contact 10, as will be apparent from the drawings.

I claim,

1. In an. electrical lamp socket, the socket body carrying the center and side plug contacts, a cap-piece, separate wire terminal plates fitted to the inner side of said cappiece and one of which wire terminal plates is of crescent form and provided at diametrically opposite terminals with threaded openings, combined fastening and conducting screws carried by the body and engaging the side plug contact, said screws detachably engaging the said threaded openings in one of the wire terminal plates, and a switch mechanism housed within the body and having a screw-connection with the center plug contact, said switch mechanism including a rotating switch block adapted to make contact with one of the fixed wire terminal plates on the cap-piece.

2. In an electrical lamp socket, the combination with the body, the plug contacts and the wire terminal connectlons, of a switch mechanism, a key-shaft carrying a switch block and atwo-part switch frame consisting of a folded contact member having a longitudinally arranged spring contact for the switch block and an angularly arranged bearing-arm, and a separate bearing member formed ofa slotted plate receiving therethrough the looped part'of the folded contact member.

3. In an electrical lamp socket, the combination with the body, the plug contacts and the wire terminal connections, of a switchmechanism, a key-shaft carrying a switch block and a two-part switch frame consisting of a folded contact member having a longitudinally arranged spring contact for the switch block and an angularly arranged bearing arm, and a separate bearing member formed'of a slotted plate receiving therethrough the looped part of the folded contact member, and a combined fastening and conducting screw engaging the overlapped parts of said contact and bearing members and connecting the latter with one of the plug contacts.

In testimony whereof I hereunto afiix my signature in the presence of two witnesses.

=ED6AR H. FREEMAN. Witnesses:

CASPER J. FABER, MARY S. CURTIS.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. C. 

